Yes, cousin marriage is legal in Missouri under specific conditions. Missouri Revised Statutes § 451.020 permits first-cousin unions if both parties are at least 50 years old or one is sterile, aligning with state public health priorities. The Missouri Department of Health and Senior Services enforces no additional prohibitions, though county clerks may request genetic counseling disclaimers in some jurisdictions.
Key Regulations for Cousin Marriage in Missouri
- Age or Sterility Requirement: § 451.020 mandates that first cousins may marry only if both are 50+ or one is medically sterile, reflecting legislative intent to mitigate genetic risks.
- No Additional State Restrictions: Unlike states such as Kentucky, Missouri imposes no further bans on second-cousin or closer marriages, deferring to federal constitutional protections.
- Local Clerical Discretion: While state law governs legality, county recorders (e.g., St. Louis County) may require supplementary documentation, such as notarized fertility affidavits, per internal procedural guidelines.
Compliance Note: Missouri’s framework remains unchanged as of 2026, with no pending legislation to expand or restrict cousin marriage rights. Legal challenges under equal protection clauses have historically failed, reinforcing the statute’s durability. Consult a Missouri-licensed attorney for county-specific variations.